Wyniki wyszukiwania - BazTech

1

Development of single-phase single switch AC-DC Zeta converter for improved power quality

Azad Ferdous S., Sarowar Golam, Ahmed Istiak

Przegląd Elektrotechniczny

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2021

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R. 97, nr 7

110--115

EN

A new topology of single–phase single switch non-isolated AC-DC Zeta converter is presented in this paper. The proposed topology in open loop operation can provide high conversion efficiency under duty cycle variation. Proposed converter with feedback controller provides high input power factor of 0.99 and reduced input THD while maintaining 900V DC output voltage. The converter exhibits stable dynamic response for sudden load change. Analysis and simulation results of the circuit are obtained using software simulation.

PL

W artykule przedstawiono nową topologię jednofazowego, jednoprzełącznikowego nieizolowanego przekształtnika AC-DC Zeta. Proponowana topologia w pracy w otwartej pętli może zapewnić wysoką wydajność konwersji przy zmianach cyklu pracy. Proponowany przekształtnik z kontrolerem sprzężenia zwrotnego zapewnia wysoki współczynnik mocy wejściowej 0,99 i zmniejszone THD wejściowe przy zachowaniu napięcia wyjściowego 900 V DC. Przetwornik wykazuje stabilną dynamiczną odpowiedź na nagłą zmianę obciążenia.

2

A buck-boost controlled full bridge LED driver with zero-voltage switching

Ramakrishnareddy Ch. Kasi, Kumar K. Ranjith, Kalavathi M. Surya

Journal of Power Technologies

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2021

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Vol. 101, nr 1

62--69

EN

A full bridge driver circuit with modulated input voltage using buck-boost converter for LED lighting systems is proposed. A dc voltage source, which is in series, processes portion of lamp power without conversion. Small controlled power is supplied through full bridge circuit. In the proposed configuration, current stress of switches in full bridge is greatly reduced. In addition, zero-voltage switching (ZVS) is accomplished in full bridge devices. Input voltage variations can be compensated to maintain constant LED lamp current. All LED lamps are dimmed simultaneously using on-off control. The circuit description and analysis are discussed in detail and it is validated experimentally.

3

Closed loop voltage mode controlled high step-down/step-up positive output buck–boost converter

Udumula Ramanjaneya Reddy, Hanumandla Deepika, Bellapu Vijayalakshmi

Journal of Power Technologies

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2020

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Vol. 100, nr 3

255--262

EN

This work presents the positive output buck-boost (POBB) converter with single loop control and simple converter structure. The presented POBB converter achieves the square of the high step-down/step-up voltage conversion gain as compared with the traditional buck-boost (TBB) converter and also the output voltage polarity is positive. These advanced features facilitate work in a wider range of high-step-down/step-up positive output converters. In the high gain POBB converter the two controlled power switches are operated synchronously. The converter is designed to operate in continuous current mode (CCM), one in switch-on mode, during which the two inductors are energized and two capacitors are discharged, and the later one in switch-off mode, during which the two inductorsare deenergized and two capacitors are charged. The operating principles and the steady-state analysis of high step-don/ step-up POBB converter operating in CCM are presented in detail. Further, a closed loop voltage mode control (VMC) is designed and simulated to study the line and load regulations of POBB converter in both high step-down (buck mode) and high step-up (boost modes) respectively. Theoretical analysis and predictions of the closed loop VMC POBB converter have been validated using MATLAB/Simulink platform.